Schematic view of the dynamics in the LIF-RET model.
Graphical representation of the matrix K with rate coefficients for all transitions.
State-to-state RET rate coefficients at room temperature as calculated by the ECS-EP scaling law, in comparison with rate coefficients as measured by Lee et al. 8 at 300 K with N2 as buffer gas at 1 mbar pressure.
State-to-state RET rate coefficients at room temperature as calculated with the ECS-EP scaling law, for the transitions where the fine structure is conserved (left) or changed (right).
Evolution of the population of the rotational states of NO A(v = 0) after the excitation of the Q 22 + Q 12(14) transition for the F 1 (left) and F 2 (right) fine structures. The black line is the Boltzmann distribution for 300 K.
Simulated population decay of the full vibrational band NO A(v = 0), and the pumped states scaled with the Boltzmann factor. After 2.9 ns all states follow the same exponential decay.
Schematic drawing of the LIF setup.
Time and wavelength resolved fluorescence and emission signal of the NO A(v = 0) → X(v = 2) transition inside the plasma at 2.0 mm axial position. At t = 0 a laser pulse excites the Q 11 + Q 21(N = 31) transition.
Wavelength integrated LIF signal of the measurement shown in Figure 8 , corrected for emission background. Note the difference in intensity (due to RET) during the first 30 ns.
Time integrated LIF spectra with excitation at 224.877 nm corresponding to the Q 11 + Q 21(31) transition. The spectra are time integrated values of the data shown in Figure 8 , corrected for plasma emission. The spectrum integrated between 40 and 50 ns is fitted, resulting in the fitted temperature parameters of 1479 ± 20 K.
Time integrated LIF spectra with excitation at 226.374 nm (Q 22 + Q 12(14) line). The spectra are time integrated during different time periods, and corrected for plasma emission. The spectra are fitted, resulting in the following fitted temperature parameters: for 0–5 ns, 429 ± 96 K; for 5–10 ns, 775 ± 27 K; and for 40–50 ns, 1442 ± 39 K (see the text for details).
Time evolution of the fitted temperature parameter for different plasma conditions, and for laser excitation at N < N max and N > N max. The circled numbers refer to rows in Table II .
Rate coefficients for NO A. The RET rates are the total rates from all transitions originating from one rotational state N q , indicated between brackets.
Results of measurements and simulation of the thermalization time at different temperatures. The row numbers refer to the circled numbers in Figure 12 , the position is the axial position in the plasma jet, the thermalization time is calculated starting from the maximum laser intensity.
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